Each antibody binds to a specific antigen; an interaction similar to a lock and key. An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shape protein produced by plasma cells that is used by the immune system to identify and neutralize pathogens such as bacteria and viruses.The antibody recognizes a unique molecule of the harmful agent, called an antigen, via the variable region.he membrane-bound form of an antibody may be called a surface immunoglobulin (sIg) or a membrane immunoglobulin (mIg). It is part of the B cell receptor (BCR), which allows a B cell to detect when a specific antigen is present in the body and triggers B cell activation.
The Beginnings Slavery in America began in 1619, meaning that was when slaves began to show up in the original colonies. However, this practice had happened even in the Spanish colonies as early as the 1560s. What has to be remembered is that slaves weren't always the way we think of them.
Follow the timeline to learn more about the history of slavery in the United States, including the arrival of the first African slaves to America, the federal banishment of slave importation, and the abolishment of slavery in the United States. The first African slaves arrive in Virginia. Slavery is made illegal in the Northwest Territory. The U.S Constitution states that Congress may not ban the slave trade until 1808.